I have shot USPSA matches with youngsters in their early teens. They invariably handled themselves in a safe and competent manner, usually shooting the same match with a parent.

One club ran a fun match under USPSA rules that had a loaner .22 for young children to use. I saw kids as young as 7 or 8 shooting the same stages as the grownups. The RO would make any necessary reloads and carry the gun while the youngster would walk between the various shooting positions. Time was not counted, only hits were scored with plaques awarded after the match. This was a big confidence builder for the kids involved.